A formation criterion for Order-Disorder (OD) phases of the Long-Period Stacking Order (LPSO)-type in Mg-Al-RE (Rare Earth) Ternary Systems.

ABSTRACT: The formation of OD (order-disorder) phases of the LPSO (long-period stacking ordered)-type in Mg-Al-RE (RE (rare earth) = Y, La, Ce, Nd, Sm, Dy, Ho, Er and Yb) ternary systems has been investigated for both as-solidified and annealed conditions. The OD phase is found to form in those systems with RE = Y, Nd, Sm, Dy, Ho and Er. The Mg-Al-RE OD phase formed is of the 18R-LPSO-type consisting of 6-layer structural blocks with the RE enrichment occurring in the four consecutive atomic layers in the structural block in the form of the Al₆RE₈ L1₂-type atomic clusters. The Mg-Al-RE OD phases are found to be stabilized by the inclusion of any atoms (either Mg, Al or RE) in the central site of the Al₆RE₈ L1₂-type atomic cluster. The

SUBMITTER: Kishida K 

PROVIDER: S-EPMC5612944 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature